IgE (Immunoglobulin E)

Immunoglobulin E (IgE) is the antibody class most closely linked to allergic disease. This test measures the total level of IgE circulating in your blood and is typically requested when a clinician suspects an allergic or atopic condition, or when symptoms such as persistent sneezing, itchy or watery eyes, wheezing, eczema, hives, or recurrent gastrointestinal upset need objective investigation. It is suitable for adults and children and is often used alongside a clinical history and, where appropriate, specific allergen testing.

The analysis is performed using a validated immunoassay technique, which provides a quantitative measurement of total IgE in the sample. A single blood sample is all that is required, collected by a trained phlebotomist.

What is measured

• Total Immunoglobulin E (IgE): The overall concentration of IgE antibodies in the bloodstream. IgE binds to mast cells and basophils and triggers the release of histamine and other mediators during an allergic response. An elevated total IgE can support the suspicion of an atopic tendency, while a normal result does not exclude allergy, as some individuals with allergic disease have total IgE within the reference range.

Why it matters

Total IgE gives a broad, quantitative signal of allergic sensitisation and can help guide the next steps in your care. It is particularly useful when symptoms are non-specific, when the clinical picture is unclear, or when a baseline measurement is needed before or during treatment. Combined with your history and any specific allergen results, it supports a more targeted approach to diagnosis and management, helping you and your clinician decide whether further allergy investigation, avoidance strategies, or treatment is appropriate.